It only took a few materials to fill up my math shelf. Rocks, rulers, baskets, boxes and a scale. I gave very few instructions or examples. Most kids came up with more ideas than I could of thought of. And that is why I give no instructions. They need none.
I sent this one one up in the morning before the children arrived. It became more of a "small world" play than a math game. Even though the numbers were not used in a game that I observed, the numbers were still in there sight.
I later added some spinners to the shelf. This is the perfect example of learn through play!